In ITIL® the entity charged with approval of a Request for Change is called the Change Authority. In most environments, the identity of the Change Authority varies with the type of change under consideration. For many ordinary changes, the Change Manager may act as the Change Authority. However, for extremely large changes, the Change Authority may be an executive or even the board of directors.
Change Advisory Board
The Change Advisory Board or CAB is a group of experts convened by the Change Manager to advise on the approval/rejection and planning for a specific change. The membership of the CAB usually varies with the change under consideration.
Emergency Change Advisory Board
The Emergency Change Advisory Board or ECAB is a special group convened by the Change Manager to advise on the approval/rejection and planning for Emergency Changes as part of the Emergency Change Management Process. The membership of the ECAB usually includes persons with the experience and
organizational authority required to make rapid and often difficult decisions and to accept the consequences of those decisions.
A Change Model is a template or pre-defined set of steps, procedures, and guidelines for execution a specific type of change. Change Models are used to help minimize risk, save costs, and improve the consistency of execution around changes.
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